JPH048543Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] This invention relates to a tape cartridge that is characterized by a means for optically detecting the end of the tape. This prevents tape end detection from malfunctioning due to external light entering the case.

[Background technology]

The drawing shows an example of a video tape cartridge, which consists of a main body case 1 which is made up of upper and lower cases 1a and 1b joined together with lids, and tape reels 3 and 3 on which tape 2 is wound on the left and right sides of the case bottom. A tape loading pocket 5, which is rotatably mounted and positioned over each transparent drive shaft insertion hole in the wall 4, is inserted into the front side of the main body case 1, and is open at the front and bottom. The tape 2 passes through the front surface of the pocket 5 fed out from one tape reel 3 and is wound onto the other tape reel 3. A front cover 6 is pivotally attached to the front of the main body case 1 so that it can be opened and closed, and a transparent window 8 is formed on the upper wall 7 of the main body case 1 to visually check the amount of tape 2 wound on each tape reel 3. A reel brake means 9 is provided at the rear central portion of the case 1.

When the tape cartridge is not in use, the front cover 6 covers and protects the front outside of the tape 2.
A reel brake means 9 locks the rotation of each tape reel 3 to prevent the tape 2 from loosening toward the front of the case. When the tape cartridge cartridge is loaded into the player, the front lid 6 is rotated upward and the reel brake means 9 is disengaged, allowing each tape reel 3 to rotate freely, allowing the player's tape to enter the pocket 5 from below. The tape 2 is pulled out to the front of the case by the loading pin 10.

Among such tape cartridges, there is one in which the beginning and end of the tape are automatically detected optically when loaded into a player. There, the player's side projector 1 is placed in the front part of the main body case 1.
2 is provided from the bottom of the case, and player-side light receivers 14, 14 are arranged on the lateral outer sides of the left and right side walls 13, 13 of the main body case 1, and the left and right side walls 13 of the main body case 1 , through hole 1 in 13
5 and 15, respectively, and constitute a tape end detection optical path L in which a detection hole from the light emitter 12 passes through the tape 2, passes through the through hole 15, and is received by the light receiver 14. The starting and ending ends of the tape 2 are detected using transparent leader tapes connected to both ends of the tape 2.

In the present invention, the problem is the position setting of the light emitter 12 and the light receiver 14 regarding this tape end detection means.

That is, FIG. 1 shows a conventional example, in which a through hole is formed in the front central part of the case bottom wall 4 as an opening 16 that allows the projector 12 to enter therein, but there is no hole between it and the tape loading pocket 5. For this reason, the projecting position of the projector 12 is set close to the center of the front and back of the main body case 1. Therefore, in order to avoid interference with the tape winding layer wound around each tape reel 3, the left and right light receivers 14, 14 are arranged obliquely in front of the projecting position of the light projector 12.

In such a conventional form, the light receiving surface 14 of each light receiver 14
A is arranged to face the transparent window 8 provided on the upper wall 7 of the main body case 1. In this case, when the external light entering the main body case 1 through the transparent window 8 is strong,
The light receiver 14 may receive this external light and malfunction.

Such a problem may occur even if the openings 16, 16 into which the projector 12 enters are provided on the left and right sides of the front end of the case bottom wall 4, the projector 12
The same problem occurs as long as the detection light from the is projected diagonally forward.

However, in the past, although there was a strong interest in preventing malfunctions in tape end detection, no attention was paid to the positional relationship between the emitter 12 and the receiver 14 on the deck side with respect to the tape cartridge, and the opening was wasted. 1
The conventional technique has been to provide some kind of light-shielding wall to prevent outside light from entering the transparent window 8 into the outer periphery of the tape end detection optical path L and the tape end detection optical path L.

[Purpose of invention]

From this point of view, the present invention has made a fundamental review of the existing tape end detection means, reliably prevents malfunctions caused by external light from the transparent window 8, and has been designed to The purpose is to ensure a large degree of freedom.

[Summary of the idea]

In order to achieve the above object, the present invention has a structure in which the projector 2 is inserted into the front part of the main body case 1 and the receiver 14 is arranged on the lateral outer side of the left and right side walls 13 of the case, and the projector is placed on the deck side. 12
The projecting position of the projector 12 relative to the main body case 1 with respect to the tape end detection optical path L connecting the tape end detection optical path L connecting the tape end detection optical path L and the light receiver 14 is set so that the light receiving surface 14a of the light receiver 14 faces the transparent window 8. . In other words, the detection light from the light projector 12 is projected diagonally backward. Here, when the light receiving surface 14a of the light receiver 14 turns its back to the transparent window 8, it is impossible to completely turn its back to the transparent window 8 due to the arrangement relationship between the light projector 12 and the light receiver 14, and the light receiving surface 14a of the light receiver 14 turns away from the transparent window 8. In terms of the relationship with the case 1, this means that it is sufficient to face the front of the main case 1. The limit range also includes a state in which the light receiving surface 14a faces the left and right side walls 13 of the main body case 1 at right angles, that is, a state in which the horizontal axis of the transparent window 8 and the tape end detection optical path L are correctly parallel.

[Embodiment 1] FIGS. 2 and 3 show a first embodiment of the tape cartridge according to the present invention, the basic structure of which is as described above.

The tape loading pocket 5 has a large opening formed almost between the left and right sides of the front of the case, and allows the player's side projectors 12 to enter from below into the left and right corners of the deep inside of the pocket 5. . Then, the light receiver 14,1 on the player side
Reference numeral 4 is located on the rear side of the case relative to the entry position of the projectors 12, 12, and on the lateral outer side of the left and right side walls 13, 13.

In such a case, with the tape cartridge loaded in the player,
The projection detection light from 2 and 12 is transmitted only through the transparent leader tape portion of the tape 2, and is further transmitted through the through hole 1.
The light is received by the light receivers 14 and 14 via the light beams 5 and 15. At this time, the tape end detection optical path L is inclined by a certain angle (approximately 23 degrees in the figure) with respect to the horizontal axis of the main body case 1, so that the light receiving surface 14a of each light receiver 14 is at the center of the main body case 1. It faces forward and has its back to the transparent window 8. As a result, transparent window 8
External light that enters the main body case from the outside is not received by the light receiver 14, so that malfunction does not occur.

The through holes 15, which are transparently provided in the left and right side walls 13 of the main body case 1, are closed by connecting pieces 6a of the front lid 6 when not in use, as shown in FIG.
When the front lid 6 is rotated to open upward, the inside and outside are communicated.

[Embodiment 2] FIG. 4 shows a second embodiment of the present invention, in which the projector 12 also enters the pocket 5 from below. However, the projecting position of the projector 12 is set in the center of the front end of the pocket 5 away from the projecting position of the tape loading pin 10, and the projecting position of the projector 12 is set at the left and right center of the pocket 5, away from the projecting position of the tape loading pin 10. Detection light is projected onto the light receivers 14, 14 of.

[Embodiment 3] Fig. 5 shows a third embodiment of the present invention, in which two dedicated openings 16, 16 for entering the floodlight are provided in the front central part of the bottom wall 4 of the main body case 1, on the left and right sides. Provided for. However, the openings 16, 16 protrude forward within a range that does not contact or interfere with the insertion position of the tape loading pin 10, and the length from the front end of the main body case 1 to the opening 16 is smaller than in the conventional example shown in FIG. The distance is set to be as short as possible, so that in this example as well, the tape end detection optical path L is such that the projection direction of the detection light is diagonally backward by a certain angle with respect to the horizontal axis.

[Modified example]

As can be seen from the above representative embodiments, the present invention is such that the projection direction of the detection light from the projector 12 is parallel to the horizontal axis of the main body case 1 or diagonally backward, and the tape Edge detection optical path L
As long as is set in this way, the projecting position of the projector 12 relative to the front part of the main body case 1 may be located anywhere on the optical path L.

Further, the transparent window 8 may be dividedly arranged on the left and right sides of the case top wall 7, or may be provided only on one of the left and right sides.

Needless to say, the shape of the tape loading pocket 5 may be divided into left and right portions at the front of the main body case 1, as seen in, for example, a conventionally known VHS type video tape cartridge.

[Effect of idea]

As explained above, according to the present invention, with respect to the tape end detection optical path L, the projecting position of the projector 12 with respect to the front part of the main body case 1 is determined so that the light receiving surface 14a of the light receiver 14 is at least parallel to the horizontal axis of the main body case 1 or at the front of the case. Since the direction is set so that the back is to the transparent window 8, the external light from the transparent window 8 provided on the case top wall 7 is directed to the light receiving surface 14 of the light receiver 14.
There is no possibility that the tape will be incident on the tape end, and erroneous operation of tape end detection can be effectively and reliably prevented. This also means that it is possible to make the transparent window 8 large in order to easily visually check the amount of tape wound on the tape reel 3, and in this respect as well, it is possible to provide a product that is easy to use. It is.

In addition, as long as the above conditions are satisfied, the projecting position of the projector 12 can be freely set on the tape end detection optical path L. Therefore, for example, on the main body case 1 side, the pocket 5 is wide on the left and right sides and has a large recessed shape, as shown in the example shown in the figure. When the pocket 5 is formed in the same manner as shown in FIG. Accordingly, on the player side, the projector 12 can be placed at a position where there is no problem especially in relation to the tape loading pin 10, so there is a large degree of leeway in design, which is advantageous in this respect as well.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway plan view showing a conventional tape cartridge. 2 and 3 show a first embodiment of the tape cartridge according to the present invention, with FIG. 2 being a partially cutaway plan view and FIG. 3 being a right side view thereof. FIG. 4 is a plan view of the main parts of a second embodiment of the tape cartridge according to the present invention. FIG. 5 is a plan view of the main parts of a third embodiment of the tape cartridge according to the present invention. 1... Body case, 2... Tape, 3... Tape reel, 4... Bottom wall of main body case, 5... Tape loading pocket, 7... Top wall of main body case, 8... Transparent window, 12... Floodlight, 13...
...Left and right side walls of the main body case, 14...Receiver, 14
a... Light receiving surface of light receiver, 15... Through hole, 16...
Opening, L...Tape end detection optical path.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A transparent window 8 is provided on the top wall 7 of the main case 1 that houses the tape reel 3 on which the tape 2 is wound, and the front part of the main case 1 is provided with a transparent window 8 for visually checking the amount of tape wound. The tape end detection light from the projector 12 passes through the through hole 1 provided in the left and right side walls 13 of the main body case 1, which has an opening that allows the entry of the projector 12 on the player side.
In the tape cartridge, the light is received by the player-side light receiver 14 disposed on the outer side of the left and right side walls 13 via the light projector 1.
2 and the light receiver 14, the projecting position of the projector 12 relative to the main body case 1 is set such that the light receiving surface 14a of the light receiver 14 faces away from the transparent window 8. Features a tape cartridge. (2) The tape cartridge according to claim 1, wherein the projecting position of the projector 12 relative to the main body case 1 is within the tape loading pocket 5 recessed in the front surface of the main body case 1.